1. Technical Field
The present disclosure relates to a speech recognition method, a speech recognition apparatus, and a non-transitory computer-readable recording medium storing a program.
2. Description of the Related Art
Technology that uses a sound pickup device such as a microphone to recognize a specific speech signal, or in other words, speech recognition technology, has been proposed. For example, Japanese Unexamined Patent Application Publication No. 7-336790 discloses a microphone system that uses multiple directional microphones in a sound field where multiple speakers are present to pick up a specific speech signal. In the microphone system described in Japanese Unexamined Patent Application Publication No. 7-336790, each microphone is disposed toward a speaker. Furthermore, from among the speech signals from the respective microphones, the speech signal having a speech signal level that exceeds the noise level in the silent state the earliest is selected and output.
The microphone system described in Japanese Unexamined Patent Application Publication No. 7-336790 is provided with a delay element that delays the speech signal to reduce the loss of the start of speech, in which the beginning of a word goes missing due to the speech signal processing time. The speech signals from the multiple microphones are selected for output after being amplified by an amp and passing through the delay element.
In addition, the amount of delay is taken to be the maximum amount of delay from among the amounts of delay due to various speech signal processing elements in the microphone system.